Is There a Connection Between Low Testosterone and Transgender Transition?
by Benjamin Bunting BA(Hons) PGCert
Written by Ben Bunting: BA, PGCert. (Sport & Exercise Nutrition) // British Army Physical Training Instructor // S&C Coach.
When considering the side effects of hormone therapy, one of the key questions is, "Is there a connection between low testosterone and transition?" Estrogens are the mainstay of hormone therapy for transgender women, and they are responsible for a number of physiological effects, including suppression of breast development and gonadotropin secretion. While transgender women do experience some side effects, the benefits of these drugs far outweigh the risks.
Estrogens are the mainstay of hormone therapy for transgender women
Hormone therapy for transgender women aims to feminize the patient by changing the pattern of fat distribution, inducing breast formation, and reducing male pattern hair growth. The primary hormones used in transgender hormone therapy are estrogens. Exogenous estrogens suppress the pituitary gland's production of gonadotropin, which lowers androgen production. In transgender patients, estrogen alone is usually insufficient to suppress androgen production. Anti-androgenic therapy must be used in addition to estrogen to suppress androgen production.
While the association between estrogen and cardiovascular disease is not conclusive, studies of estrogen and transwomen show a trend toward increased risk. Oral ethinyl estradiol was linked to an increased risk of cardiovascular events and should not be used as a mainstay therapy in transgender patients. Diabetes is a significant risk factor for cardiovascular events, so patients taking estrogen should be monitored for it.
There are several potential risks associated with feminizing hormone therapy, especially when initiated before puberty. For transgender women, the risk of permanent infertility increases significantly. Without reproductive technology, the testicles may not recover to the extent needed to ensure conception. For this reason, transgender women who want to have biological children should discuss sperm cryopreservation with their doctors. However, estrogen use in transgender women also has other side effects that can compromise a woman's sexual ability and libido.
Estrogens suppress gonadotropin secretion
Endocrinologists often work in collaboration with mental health professionals to ensure proper hormone treatment. Their primary objective is to suppress endogenous sex hormone levels and achieve desired gender hormone characteristics. The amount of estrogen prescribed to a patient will depend on their needs. There are several types of hormone replacement in the market today. If you are interested in hormone replacement therapy for transgender women, here are some of your options:
A hormone called GnRH stimulates the release of luteinising hormone and follicle-stimulating hormone, thereby maintaining homeostatic balance. The pituitary gland also receives feedback from T and inhibin-B. In humans and primates, androgens suppress LH synthesis by inhibiting the GnRH pulse generator. However, hormones are required for sexual function and development. Therefore, hormone replacement therapy is required in transgender women.
The treatment of transgender women can take place in two phases. The first stage of this phase involves suppressing puberty. During this phase, estrogen receptors become desensitized and gonadotropin secretion declines. In transgender women, however, the treatment may lead to regressive sexual development. However, there are advantages to the treatment approach.
Estrogens and blood pressure
Transgender women who take hormones may face higher risks for heart attacks and strokes. The hormone is also associated with an elevated risk for venous thromboembolism, a blood clot that can travel to the lungs. According to research, transgender women taking estrogens face a nearly 80 percent increased risk of heart attacks and a 355 percent higher risk for VTE than cisgender women. It may be difficult to stop hormone treatment, and there are significant psychological side effects that can make the process difficult to manage.
The effects of estrogen on blood pressure in transgender women were compared with those in transgender men. Although estrogen decreased SBP in transgender men, it increased it in transgender women. These results suggest that hormones may have a protective effect on transgender women by suppressing their BP. While GHT may suppress BP in transgender men, it does not have this effect in transgender women.
The main class of hormone therapy for transgender women is estrogen-lowering hormone therapy. Before 2003, synthetic estrogen, EE, was widely used. However, safety concerns prompted the switch to estradiol valerate. Although more studies are needed, the Endocrine Society guidelines recommend serum estradiol concentrations of 100-200 pg/ml and 367.1-743 pmol/l, respectively.
Estrogens suppress breast development
Although there's not much research on whether estrogens suppress breast development in transgender women, some preliminary findings indicate that the hormones can interfere with the development of breasts in transgender women. The study authors, from the University of Massachusetts Amherst in Massachusetts, found that about half of the trans-women enrolled in the study were below the average AA cup size, or 8 centimeters. The remaining 26 percent had a bra cup size of an AA or AAA, which would correspond to a cup size of eight to 10 centimeters. After accounting for the size of the breasts at the start of the study, however, the average growth in breast size did not change.
In addition to the effects of spirolactone and estrogens, the antiandrogen cyproterone acetate is not associated with an increased risk of breast development in trans women. In contrast, trans-womenwomen who take spirolactone, a common antiandrogen, have a higher risk of breast augmentation than women who take progesterone. However, the benefits of progesterone and GnRH analogues are not as clear.
Besides a high risk of pulmonary embolism, estrogens suppress breast development in transgender women. The hormones are prothrombotic, which means they increase blood clotting. The risk of pulmonary embolism (PE) increases after DVT and PE. Both have similar symptoms - swelling of the calf and chest pain. While a single symptom of DVT is painful, an occurrence of PE will be marked by a clear bilateral nipple discharge.
Estrogens suppress libido
The problem with estrogen is that it feminizes the penis, causing shorter erections, a softer texture, and atrophy. While this is a real problem, transgender women should not panic. While it is true that trans women have more genitalia than a cis man's, the effects are not as severe as the widespread myth would suggest.
Although there are few well-designed studies on the effects of progestogens, many transgender women report improvements in mood and breast development after taking them. Progestogens can have a mixed response on transgender patients. In addition to an anti-androgen effect through central blocking of gonadotropins, they may also have a direct androgenizing effect. Progestogens include micronized bioidentical progesterone and synthetic progestins.
A study of transsexual women who were ovulating found a positive correlation between serum androgen levels. However, it did not find a positive association between androgens and libido. Although transsexual women have lower testosterone levels than the general population, most have low levels of both hormones. There is no definitive way to determine whether or not estrogens suppress libido, but a lack of studies is an important starting point.
Estrogens suppress brain phenotype
One of the important questions in transgender neuroscience is whether the effects of estrogens on the brain are relevant in MTF. Interestingly, estrogens suppress a number of sex-related behaviors. These include anger, aggression, sexual interest, verbal fluency, and spatial abilities. Furthermore, estrogens suppress MTF cognitive outcomes, including anger and aggression, but little is known about their broader impact on gender-specific behaviors.
Recent research indicates that sex hormones and steroids exert an organizational influence on brain morphology during prenatal and peri-pubertal development. This organization can extend to the brain later in adulthood, when it is fully formed. While most research has focused on vascular and epithelial systems, it has neglected the central nervous system. This is reflected by the altered bone geometry and increased ventricular size in transgender women after anti-androgen treatment.
Although the distinction between the male and female brain is well-defined, gender is not always clearly defined. Some brain regions may be more or less programmed by estrogens than by androgens. Additionally, greater or lesser masculinization occurs during prenatal development, which leads to a mosaic of male and female brain phenotypes. Although these findings have limited clinical relevance, they indicate the importance of adversity-related influences in transgender brain development.
Other research has shown that androgens influence FTM cognitive performance. After three months of treatment, there were significant improvements in spatial ability but deterioration in verbal fluency. In a larger sample of FTM and MTF transgender individuals, androgen administration strongly affected aggression, sexual arousal, and cognitive functioning in transgender individuals. Therefore, the question is: Do estrogens affect brain phenotype in transgender women?